In the process of preparation for the JEE main exam, students are expected to focus on scoring subjects like physics, chemistry and mathematics. Each subject has the same weightage thus each subject must be studied with similar efforts and given enough time for practice as well as revision. If a student feels that he/she needs extra work on a certain subject then the study schedule must include extra time for that subject. Also, it’s not right to completely ignore your weaker subject and only focus on strong subjects. A student must have knowledge of all three subjects in order to score excellent marks in the JEE main exam.
Chemistry is one of the important scoring subjects in the JEE main exam. Even if there are many students who take chemistry subject lightly, it is still crucial to practise important reactions, formulas and concepts for the JEE main exam. Chemistry subject is split into physical chemistry, organic chemistry and inorganic chemistry.
Tips to score in Chemistry JEE main exam
The key to studying well in a chemistry subject is knowing all organic chemistry chapters along with inorganic chemistry chapters. Never skip any topic in organic chemistry as everything is correlated with each other. It’s vital to clear the basic concepts before learning lengthy chemistry reactions. Chemistry has a vast portion to cover in the JEE main exam in which some topics are easy to understand and remember. Also, every chemistry chapter has a different weightage from an exam perspective.
Create a study schedule based on the weightage and importance of each chapter. Every chemical reaction or formula should be practised multiple times. There are several important chemistry questions for JEE main that must be included in regular learning.
The important question from important chapters in Chemistry
Chemical Bonding and Atomic structure
- Kossel – Lewis for chemical bond formation
- Ionic bonding and covalent bonds.
Formation and factors affecting the ionic bonds. Calculation of lattice enthalpy.
- Covalent Bonding
Theory of electronegativity, the concept of Fajan’s rule, questions on dipole moment.
Theory of Valence Shell Electron Pair Repulsion theory and questions on shapes of simple molecules. Quantum mechanical concept of covalent bonding
- Questions on valence bond, s, p and d orbitals concept of hybridization and resonance.
- Molecular Orbital Theory
Important features of MOT and its types. Bonding, antibonding, bond length, the concept of bond order and bond energy.Sigma and pi-bonds, molecular orbital electronic configurations.
- Metallic bonding, hydrogen bonding and its applications.
- Bohr model, the spectrum of the hydrogen atom and quantum numbers.
- Concept of wave-particle duality and de Broglie hypothesis.
- Theory of uncertainty principle and qualitative quantum mechanical picture of the hydrogen atom. Study questions related to shapes of s, p and d orbitals. Learn electronic configurations of elements.
- Theory of Aufbau principle.
- Concept of Pauli’s exclusion principle and Hund’s rule.
- Study orbital overlap and hybridisation of s, p and d orbitals.
Periodic table
- Periodic Classification and Periodicity in Properties
- Classification of elements
- Theory of Law of Triads and Law of Octaves
- Study Mendeleev’s Periodic Table and Modern Periodic Table. Characteristics and factors of Modern Periodic table. Periodic trends that explain changes in properties of elements etc.
Redox reactions, Mole Concept and Electrochemistry
- Concepts of electronic oxidation and reduction.
- Theory of redox reactions, the concept of oxidation number, rules for assigning oxidation number and balancing of redox reactions.
- Electrolytic and metallic conduction
- Conductance in electrolytic solutions and molar conductivities along with variation in concentration.
- Theory of Kohlrausch’s law and its applications.
- Working and theory of Electrochemical cells that consist of Electrolytic and Galvanic cells.
- Types of electrodes and standard electrode potentials.
- Concept of half-cell and cell reactions. Theory and calculation of emf of a galvanic cell.
- Nernst equation and its applications, fuel cell, dry cell and lead accumulator.
Solid-state, solutions and gases theory
- Classification of solids
- Theory of molecular, ionic, covalent and metallic solids. Concept of amorphous and crystalline solids.
- Bragg’s Law and its applications.
- Calculation of unit cell and lattices, packing in solids voids and imperfection in solids.
- Electrical and magnetic property applications.
- Molality, molarity, mole fraction and percentage vapour pressure of solutions.
- Concept of Raoult’s Law Ideal and non-ideal solutions. Theory of vapour pressure composition.
- Theory of colligative properties of dilute solutions, relative lowering of vapour pressure, depression of freezing point, the elevation of boiling point and osmotic pressure.
- Concept of molecular mass using colligative properties and calculation of the abnormal value of molar mass and study of van’t Hoff factor.
Thermochemistry
- Study the fundamentals of thermodynamics. Concepts related to extensive and intensive properties, state functions, types of processes.
- Concept of the first law of thermodynamics. Theory and formula of work, heat internal energy and enthalpy, heat capacity, molar heat capacity. Concept of Hess’s law. Study of enthalpies in bond dissociation and combustion formation.
- Theory of atomization, ionization, sublimation, hydration, phase transition and solution.
- Theory of second law of thermodynamics. Concept of the spontaneity of processes.
Chapters that are easy to score:
In chemistry, there are certain chapters or topics which are easy to understand. Such chapters are usually completely based on theory and concepts which requires less time to revise. Chapters like mole concept, coordination chemistry, alcohols, phenols, and ethers and P-block elements.
Tricky but important chapters
Some chapters are tricky with lengthy syllabus like Transition Element and Coordination Chemistry. These chapters hold more weightage in JEE main exam, each year at least 3 questions are asked on an average in the exam. Chapter of Periodic Table and Representative Elements must be studied thoroughly.
Conclusion
Important Chemistry Questions For JEE Main must be practised daily with enough revision. Solve previous years JEE main question papers to know the question structure and paper pattern. Seek out online study sources to understand the paper structure for including important chemistry questions in the daily study schedule.
Chemistry is a subject with vast portion and numerous laws, theories that change according to elements or factors. All the types of exceptions must be studied well. Some students find chemistry easy, simple while some think it is tricky and difficult. Practise chemistry until it is well understood, clear your doubts, solve sufficient questions related to the above-mentioned topics and you are all set to score excellent marks in chemistry.